When Monitored
WARNING: This page is about a different car, the 2016 Dodge Journey and 2015 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
TEST No. 1: With the ignition on, the fuel level is compared to the previous key down after a 20 second delay. TEST No. 2: The PCM monitors the fuel level at ignition on.